US5053369A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sintered microcrystalline ceramic material
Assignee: Treibacher Chemische Werke AG
•
Filing: 1989-10-25
•
Granted: 1991-10-01
•
Expires: 2009-10-25
Abstract
Abstract Sintered microcrystalline ceramic material based on alpha -Al2O3 with an addition of 0.01 to 2.0 weight percent of a cerium compound, consisting of a microcrystalline matrix and 0.1 to 30 volume percent whisker-like needles, whereby said cerium compound is mainly present in the needles. The whisker-like needles give this material a special tenacity combined with good abrasive results.
Inventors
- 👤 Herwig Winkler
- 👤 Peter Janz
- 👤 Georg Gottschamel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 06:34
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/01; C04B35/10; C04B35/111; C04B35/71; C04B35/78; C04B35/80
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
58 words
Sintered microcrystalline ceramic material based on α-Al 2 O 3 with an addition of 0.01 to 2.0 weight percent of a cerium compound, consisting of a microcrystalline matrix and 0.1 to 30 volume percent whisker-like needles, said needles having a cerium content of up to 20 weight percent, whereby said cerium compound is mainly present in the needles.
Claim 2
Dependent Claim
58 words
Sintered microcrystalline ceramic material based on α-Al 2 O 3 with an addition of 0.01 to 2.0 weight percent of a cerium compound, consisting of a microcrystalline matrix and 0.1 to 30 volume percent whisker-like needles, said needles having a cerium content of up to 20 weight percent, whereby said cerium compound is mainly present in the needles.
Claim 3
Dependent Claim
58 words
Sintered microcrystalline ceramic material based on α-Al 2 O 3 with an addition of 0.01 to 0.5 weight percent of a cerium compound, consisting of a microcrystalline matrix and 1 to 25 volume percent whisker-like needles, said needles having a cerium content of up to 20 weight percent, whereby said cerium compound is mainly present in the needles.
Claim 4
Dependent Claim
58 words
Sintered microcrystalline ceramic material based on α-Al 2 O 3 with an addition of 0.01 to 0.5 weight percent of a cerium compound, consisting of a microcrystalline matrix and 1 to 25 volume percent whisker-like needles, said needles having a cerium content of up to 20 weight percent, whereby said cerium compound is mainly present in the needles.
Claim 5
Dependent Claim
58 words
Sintered microcrystalline ceramic material based on α-Al 2 O 3 with an addition of 0.01 to 0.5 weight percent of a cerium compound, consisting of a microcrystalline matrix and 1 to 15 volume percent whisker-like needles, said needles having a cerium content of up to 20 weight percent, whereby said cerium compound is mainly present in the needles.
Claim 6
Dependent Claim
58 words
Sintered microcrystalline ceramic material based on α-Al 2 O 3 with an addition of 0.01 to 0.5 weight percent of a cerium compound, consisting of a microcrystalline matrix and 1 to 15 volume percent whisker-like needles, said needles having a cerium content of up to 20 weight percent, whereby said cerium compound is mainly present in the needles.
Claim 7
Dependent Claim
13 words
Ceramic material according to claim 1, wherein the cerium compound is an oxide.
Claim 8
Dependent Claim
19 words
Ceramic material according to claim 1, wherein the needles have a cerium content of up to 10 weight percent.
Claim 9
Dependent Claim
19 words
Ceramic material according to claim 2, wherein the needles have a cerium content of up to 10 weight percent.
Claim 10
Dependent Claim
19 words
Ceramic material according to claim 3, wherein the needles have a cerium content of up to 10 weight percent.
Claim 11
Dependent Claim
70 words
Sintered microcrystalline ceramic material based on α-Al 2 O 3 with an addition of 0.01 to 2.0 weight percent of a compound of an element selected from the group consisting of Ce, La, Nd and Pr consisting of a microcrystalline matrix and 0.1 to 30 volume percent whisker-like needles, said needles having an element content of up to 20 weight percent, whereby said compound is mainly present in the needles.
Claim 12
Dependent Claim
70 words
Sintered microcrystalline ceramic material based on α-Al 2 O 3 with an addition of 0.01 to 2.0 weight percent of a compound of an element selected from the group consisting of Ce, La, Nd and Pr consisting of a microcrystalline matrix and 0.1 to 30 volume percent whisker-like needles, said needles having an element content of up to 20 weight percent, whereby said compound is mainly present in the needles.
Claim 13
Dependent Claim
15 words
Ceramic material according to claim 1, wherein the crystallite size is less than 0.5 μm.
Claim 14
Dependent Claim
15 words
Ceramic material according to claim 2, wherein the crystallite size is less than 0.5 μm.
Claim 15
Dependent Claim
15 words
Ceramic material according to claim 3, wherein the crystallite size is less than 0.5 μm.
Claim 16
Dependent Claim
15 words
Ceramic material according to claim 7, wherein the crystallite size is less than 0.5 μm.
References Cited (Backward Citations)
US3802893A
Cited
US4598053A
Cited
US4181532A
Cited
EP0024099B1
Cited
US4449989A
Cited
US4457767A
Cited
EP0152768B1
Cited
US4744802A
Cited
US4702970A
Cited
EP0293163A2
Cited
EP0293164B1
Cited
US4852999A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-09-30 | 1995-04-01 | 1995-10-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-09-30 | 1999-04-01 | 1999-10-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-09-30 | 2003-04-01 | 2003-10-01 | $7700.00 | Window Closed / Lapsed |